Returning Player

Hey everyone hoping for some guidance. & insight. I played WOW between 2007-2013ish and am hoping to return maybe next month.I just haven’t quite got my head around on how it all works now with levelling and making your way through the game. Can you still level up like in the classic WOW or has it changed to a more streamlined approach? I would love to go through azeroth again and the burning crusade.Any guidance would be much appreciated!